Abstract: Provided is a magnesium-air fuel cell in which a conductive state is achieved when a lid is fastened, and a nonconductive state is achieved when the lid is loosened, so that the power supply can be turned ON and OFF based on a fastening state of the lid. A lid includes a lower end portion that comes into contact with a main body at a time of fastening, an anode body inserted in the main body, and an electrode plate made of metal coupled to an end of the anode body. The electrode plate includes a first terminal at least positioned at the lower end portion. The main body includes a second terminal positioned on a surface that comes into contact with the lower end portion of the lid at the time of fastening the lid. Electrical conduction is achieved when the first terminal and the second terminal come into contact with each other.

Abstract: A magnesium-air fuel cell includes, in an inner portion, a pair of cathode accommodating portions each having at least one end opened. Cathode bodies are each disposed in a corresponding cathode accommodating portion, while having a part exposed to the inner portion. The part of each cathode body is separated from and faces an anode body. A power supply device using the fuel cell includes a supporting portion including a water supply port for the reaction liquid, a base portion incorporating the fuel cell, and a main body including a water supply pipe from the water supply port to the base portion. The water supply pipe is in communication with a water injection port in the fuel cell, and the water supply pipe incorporates a discharge pipe that extends from the supporting portion into the inner portion of the fuel cell and discharges reaction gas produced in the inner portion.

Abstract: Provided is a highly water repellent, air permeable, and liquid leakage resistant magnesium-air fuel cell that can quickly achieve a discharge reaction peak and can discharge a predetermined amount of current for a relatively long period of time. In a magnesium-air fuel cell, a cathode body includes: a first layer including a porous body formed by mixing a conductive carbon material and fluororesin; and a second layer including a porous body formed by mixing activated carbon and fluororesin, the second layer being joined to one surface of the first layer to be in contact with reaction liquid in the outer frame.

Abstract: A liquid leakage detection system requiring no power supply from an outer source and configured to be relatively simple and moderate in price. A liquid leakage detection system (10) including an infusion tube (11), a syringe needle (12) coupled to the infusion tube (11), an absorbent element (16) adapted to be placed in the vicinity of a point (12a) of the syringe needle (12) to be pricked through a patient skin and a sensor unit (14) located on an upper side or within the absorbent element (16).

Abstract: A liquid leakage detection system requiring no power supply from an outer source and configured to be relatively simple and moderate in price. A liquid leakage detection system (10) including an infusion tube (11), a syringe needle (12) coupled to the infusion tube (11), an absorbent element (16) adapted to be placed in the vicinity of a point (12a) of the syringe needle (12) to be pricked through a patient skin and a sensor unit (14) located on an upper side or within the absorbent element (16).